Esther Inglis-Arkell

Physicists constructed a clapping machine that quickly compressed a volume of water so that they could study the spray. It made for a very beautiful image, and some interesting physics.

Physicists presenting at the American Physical Society meeting discussed their "wet hands clapping machine." The machine was a piston that drove together two flat surfaces, with silicon oil in between them. They then studied the way that the liquid moved as it splattered outward. As part of their study, they got the above image of a wavy skirt of liquid falling around the machine.

The scientists found that the liquid passes through several distinct stages. At first the liquid shoots out in a sheet, while forming a thickened rim at the edges. Instabilities in the liquid then give create waves in the edge of the rim - which is what we're seeing here. At last, the sheet breaks up into single drops, and long strings of liquid, which fall to the ground.